On September 13 and 14, 2010, MedPAC met to discuss a variety of Medicare policy issues, including the following: the context for Medicare payment policy; Medicare’s shared savings program for accountable care organizations (ACOs); recent changes that affect Medicare beneficiaries’ financial liability; retainer-based physician practice; Medicare’s authority to apply least-costly alternative policies; growth in hospital observation care; the growth of ancillary services in physicians’ offices; and accountability for DME, home health, and hospice services.